There were times at the Dive Bar last Thursday night when you could close your eyes and imagine you had transcended back in time and dropped into the audience at Cream’s farewell show at London’s Royal Albert Hall in 1968 or a London nightclub where Jimi Hendrix and friends were jamming on the Beatles recording that came out earlier that day.

Musicians have channeled music from the past since the first instrument changed hands and phonograph records brought the sound of jazz and the blues around the world at the start of the 20th century. But few have taken on as many genres, and done so expertly, as the musicians who performed during the Dive Bar Thursday Night Music Series over the past six years.

THE LAST THURSDAY

Many in the crowd have the experience of being onstage with the band — because they are, everyone’s beers dangerously close to all the amps and sound equipment. As trombonist Jeff Galindo waits to add his magic to the mix, the close-knit quarters suggests he could decapitate one of the audience members with one wrong move. “I’ve learned how to keep my eyes open for people,” he said outside, sneaking a break on the bar’s outside patio during an extended jam.

The crowd gets louder as the group’s music effortlessly switches genres song by song — from deep southern blues to southern rock, Chicago blues fusing into British blues, morphing into the sound Deep Purple made during their early ’70s heyday, all before they break into an extended funk and soul session that includes snippets of War’s “Me and Baby Brother” and Sly and the Family Stone’s “Thank You (Falettinme Be Mice Elf Agin),” during which frontman Craig Rawding accents the line, “Different strokes for different folks,” as he whips the crowd into a frenzy.

Rawding’s vocals rose over it all. “It was a chance to be less structured and sing songs I don’t normally do or try out new lyrics over grooves that were being laid down by the band,” says Rawding, who normally fronts The Delta Generators and who teamed up with Duncan Arsenault to release “Phantom Train,” an “ambient folk rock duo album” as The Marshall Pass.

The evening’s performance had been made more urgent with the announcement earlier that week that it would be the final Dive Bar Music Series session; the audience seems determined to soak up every possible note before the night’s music comes to an end. The room is packed so tightly it’s impossible for the crowd not to brush against the musicians and their instruments, who are jimmied in as close to the area below the evening’s drink sign as humanly possible; an already vacuum-tight room gets tighter when those amassed in the outside patio area try to get inside.

“When the crowd is insanely tight like that, it can be a bit of a challenge to get comfortable but there’s also the side of it being really cool to have people be able to get close and see what we do up-close and personal,” guitarist Pete Aleksi says. “When a musician is in his element, there is little-to-no holding back of the spirit and it’s really cool to see someone let go musically.”

Through it all, Jeremy Moses Curtis’ bass playing is a vibrant all-cylinders funk attack in the style of P-Funk’s Bootsy Collins to Black Sabbath’s Geezer Butler (It doesn’t matter whether Curtis ever listened to a note of Sabbath; Butler got his start as a teen in a blues band and undoubtedly studied many of the same influences). Similarly, Aleksi’s guitar playing shows pure mastery of every style the evening’s set list throws at him, all accompanied by the steady groove laid down by keyboardist Brooks Milgate.

IN THE BEGINNING

Drummer Duncan Arsenault, who started the weekly jam sessions in August 2007, for the night, and all but three of the 300 or so that preceded it, laid down the beat. “They never had music here before,” he said of the series’ creation. “It was started due to my relationship with (owner) Alec Lopez and his philosophical ideas for his bar.”

On his Facebook page announcing the end of the series, Arsenault stated, when he fi rst pitched the idea, “I promised that if I could not put together the best group of musicians I could find that I wouldn’t play.” Initially, the Thursday nights just featured Arsenault and two other performers, usually keyboardist Steve Mossberg or late guitarist Scott Ricciuti, either together or with a special guest.

“We were really just doing duos,” Arsenault said prior to last Thursday’s finale. “Then it got out of hand with horns and big band sections.” Depending on the night, and who was in town, that included local musicians returning from a stint on the road with a national traveling act or an out-oftown musician dropping in for the evening.

THE PLAYERS

While certain musicians settled in for extended periods of time, the night was never advertised as featuring an actual band. “There were different musicians every week, playing different styles,” Arsenault says. He counted 79 musicians who played with him during the Dive Bar Series’ six-year run. He kept a list of those who performed during that time and has posted it onhttp://tinyurl.com/divethurs; he suggests people Google every name on the list, “a fascinating and rewarding musical experience” when you learn what each are currently doing along with their past accomplishments.

Keyboardist Brooks Milgate estimated he played 200 to 250 of the Thursday night shows. He had been exchanging emails with Arsenault about starting a soul band when he first sat in for a night. “The band was all friends and we would just play because we loved playing,” Milgate says. “It was a great place to try a new song that you had written or play with a new person. I wouldn’t consider it a ‘jam’ session but it was always very unscripted and spontaneous, but that was the beauty of it.”

While the lineup changed every week, the sessions weren’t traditional jam sessions where people would drop in unannounced, the bandleader would shout out a well-known song, and everyone tried to replicate the record. Arsenault says it isn’t common for clubs to host jams featuring the music that’s been played at the Dive Bar because, while many of the songs are known by many in the audience, they’re not your typical Top 40 oldies fodder everyone’s heard thousands of times since they were kids. Most of the players, put together specifi cally for that night’s show, have been serious rock ‘n’ roll, rhythm and blues and soul music audiophiles since their teens, and the songs are part of their DNA.

“You have to know the songs; not all 79 of the people who played were made for this gig,” Arsenault says. “Certain types of musicians thrive in off-the-cuff situations. Some nights, you can see the stress on people’s faces as they’re trying to play a song (they’re not fully versed in) while with others, it’s magical.”

Guitarist Pete Aleksi definitely was made for sessions like these; he played 30-40 of the nights. He reflected on how playing the Dive Bar shows compared to normal band gigs. “What made it different was the feeling of complete freedom,” he said. “Most of the music I play has a high level of improvisation, so I’m used to creating on the fly at the Dive — most of, sometimes all of — was completely made up on the spot.”

On this evening, that was most prevalent after Rawding announced, “If anyone’s going to drop acid, now’s the time,” before Curtis started the bass lines of Pink Floyd’s “Dark Side of the Moon,” which, while true to the original, had plenty of free-form creativity. It allowed everyone in the building to go on his or her own trip, with each face in the crowd processing whatever was going through their minds and bodies differently, spacing out, going on a little journey of the mind.

Keyboardist Milgate, whose full-time band, Hey Now Morris Fader, continues to support their third CD “Good Times Ne’re Forgot,” says playing all those Dive Bar shows has “really helped” his organ playing; a connection made through the series earned him a place in the recent Boston Rock ‘n’ Roll Rumble finals. After having played three Dive Bar shows, Glenn Yoder asked him to join his group, the Western States (whose album “Javelia” was produced by Curtis), for the competition, where they came in second to winner Eddie Japan.

Through playing the Dive Bar with guitarist Troy Gonyea, back in his hometown when he wasn’t on the road with the Booker T. Jones Band (of Rock ‘n’ Roll Hall of Famers Booker T & The MG’s fame), Curtis received an invitation to audition with Jones’ touring outfit; that lead to three years on the road with one of music’s alltime greats.

A UNIQUE EXPERIENCE

As the final night’s opening set neared its close, Crystal Anson of Worcester worked the room with an empty pitcher, collecting donations for the musicians. “Dive Bar Thursdays was an experience each week; it brought together great people, beer and music, especially in the summer months,” she said. “To me, it was a place I knew the closest of my friends would migrate to, the one evening a week we would get together and build memories together, surrounded by the soundtrack of the evening.”

Mike Benedetti, co-host of the 508 webcast, says it wasn’t one thing that made the series special. “It was the great beer, the changing lineup of the bands, the mix of covers and originals and songs out of left fi eld, and especially the crowd,” he says. “Just all these people who would ordinarily be out making the city a better and more exciting place, taking a break to drink and talk and sing along.”

Another aspect that gave the series its unique character was having access to an inhouse B-3 organ. “It’s a miracle to have that here,” Arsenault says. Infamous for their unforgettable sound and their weight — traditionally in the 800-pound range and a nightmare to move, Bill Connor created a portable 600-pound B-3 for use at the Dive Bar. “He saw what we were trying to do with rock, jazz, soul and funk and though it would be a good calling card for his business to do this.” Connor’s own band, The Organ Donors, was Wednesday night regulars at the bar for a spell; and he used to play Monday evenings solo.

REASON FOR THE END

So why is it all ending? “The Dive Bar decided to stop the regular Thursday series, not me,” Arsenault says. “They plan on doing special events and still have music, just not as a regular Thursday series. It’s most telling of what’s happening to live music these days.” For his part, Dive Bar owner Lopez declined responding to email questions on the legacy of the series and the reasons behind its cancellation, citing that coverage was only coming after “something so unprecedented in the scene” was ending. (Note Worcester Mag’s June, 8, 2011 story on the series’ 200th show that ran prior to the event.)

Indeed, much of the promotion for the Dive Bar Music Series was word-of-mouth, especially through Arsenault on Facebook where, over the past few weeks, he’s been sharing pictures and posters from the series. It was a reminder of how much great music had been generated during its run.

FORMED FROM THE SERIES

Along with the many memories of those special nights (Arsenault met his wife, Annie, on a Thursday night at the Dive), the legacy of the Dive Bar Music Series will be in the musical connections made and bands formed through its existence, including Beg, Scream and Shout (with many performers from the finale); Big Eyed Rabbit (with Jon Short and Jeff Burch, whose many appearances were a huge part of the series); and Pistol Whipped (featuring the late Ricciuti).

And then there’s The Curtis Mayflower, composed of Arsenault, Rawding, Milgate, Curtis and Aleksi, who brought the Dive Bar house down for the final time last Thursday. They’ve just finished recording their first album, which they plan to release by the end of the summer or start of the fall. They’ll be playing the Tweed River Music Festival in Stockbridge, Vermont this summer, as well as a handful of shows throughout New England. You can sample their “tranceincidental-blues-music” at thecurtismayflower.com.

“It’s a great band,” Curtis says. “The songs are solid, the musicianship is top-notch and I honestly could not be happier and more grateful to be part of such a group. The response from [last Thursday] leads me to believe we are doing something absolutely right.”